Speed responsive apparatus



March 12, 1940. A SORENSEN 2,193,045

SPEED RESPONSIVE APPARATUS Filed July 21, 1938 s Sheets-Sheet 1 l 102 JL105 102 JH 101 H5 9 galkl 116 I 11] [15:5 1 I a i 45' I C 129 154; I

127 155 51L 106 0 EH 1 a 1 9 1" La f if 106 L ]07(Z L INVENTOR E 691.[5. AndPea/J. P0084912.

mm ATTORNEY March 12, 1940. A. J. SORENSEN SPEED RESPONSIVE APPARATUS 5Sheets-Sheet 5 Filed July 21, 1958 INVENTOR S Andrewi 128912 ATTORNEYMarch 9 A. J. SORENSEN SPEED RESPONSIVE APPARATUS Filed July 21, 1938 5Sheets-Sheet 4 MSW INVENTOR Anafieez/J. 125012 H15" ATTOIIRNEY March 12,SQRENSEN SPEED RESPONSIVE APPARATUS 5 Sheets-Sheet 5 Filed July 21, 1938a R9 .Y mm m N R D v m \fim NR m M Qw J 5 1M m m m n A b. mm% I wmw $5 bF m mm v%% .M(%\% m mm .wmww L N a $N% \MNW 6% MN? \bfi W F F %\m. w. 7u v n n n D n in r 1 3%., Wmww WWW mw f n u m K .wN. n v N u n v u D Q ni. U ms 3 wnw j j m NN NAN MN WW. $NQ QM m .QY. b N MS Patented Mar. 12,1940 UNITED STATES PATENT OFFlCE SPEED RESPONSIVE APPARATUS ApplicationJuly 21, 1938, Serial No. 220,519

46 Claims.

My invention relates to speed responsive apparatus which is particularlyadapted for use on railway vehicles for governing the braking system ormotive power, or both, of the vehicle in accordance with its speed.

This application is a continuation in part of my application Serial No.166,378, filed September 29,1937, for Speed responsive apparatus.

While the apparatus provided by this invention is especially designedfor use on railway vehicles it is not necessarily limited to use in thisfield, and it is contemplated that the equipment may be employedwherever similar conditions are encountered.

The coefiicient of friction between a brake shoe and a car vh-eel variesinversely with the speed at which the wheel is rotating, being large atlow speeds being relatively small at high speeds. In order to obtain thebraking force necessary to properly retard a train when it is travelingat extremely high speeds, the brake equipment is designed so that thebrake shoes are pressed against the wheels with great force tocompensate for the low coeflicient of friction existing at that timebetween the brake shoes and the wheels. The degree of force employed topress the shoe against the Wheels is referred to as the braking ratio,and is measured by comparing the force availableto press the shoesagainst the Wheels of a vehicle with the weight of the. vehicle. 7 Asthe speed of the train is reduced the coeffi cient of friction. betweenthe brake shoes. and the wheels increases, and if at low speeds the samegreat force is employed to press the shoes against the wheels as at highspeeds, so much re- I tarding force will be developed between the shoesand the wheels that the Wheels will cease to rotate and will slide onthe track. 'lhisis objectionable flat spots are worn on the wheels,while adhesion between a sliding wheel and a rail much less than thatbetween a rotating wheel and a rail with the result that when the wheelsare caused to slide, the rate of retardation of the train is reduced andthe distance required for a stop is correspondingly increased.

It has been heretofore proposed, therefore, to provide means responsiveto the speed of a train or vehicle and automatically operative on areduction in the speed of the train or vehicle to reduce the brakingratio, that is, the degree of force which may be employed to press thebrake shoes against the Wheels, to a value such that wheel slicing willnot occur.

The train or vehicle speed, responsive means heretofore employed haveincorporated centrifugal devices mounted on and driven by an axle of avehicle. A device mounted on a vehicle axle is not protected orcushioned by the vehicle springs and is, therefore, subjected to thefull force of impacts on the vehicle Wheels occasioned by irregularitiesin the traclnsuch as joints between the rails, switches, crossovers andthe like. A device mounted on a vehicle axle, therefore, is subjected toconstant vibration when the vehicle is in motion. Obviously this isobjectionable in apparatus which must be sensitive to small changes invehicle speeds.

it is an object of my invention to provide speed responsive apparatusthemajor portion of which may be located at some point remote from thewheels and axles of the vehicle so that the apparatus will becomparatively free from damage due to vibration.

Any apparatus for restricting the degree of application of the brakeswhich it is possible to secure is subject to the possibility of becominginoperative. It is desired in suchcases that if for any reason theapparatus does not function in the intended manner, it willautomatically operate to permit the maximum degree of brake application,or some predetermined degree of brake application greater than theminimum.

vIt is desirable, therefore. that any electrical speed responsivemechanism operate on the closed circuit principle, that is, that it beconditioned when deenergized topermit the maximum degree of brakeapplication or the predetermined degree in excess of the minimum. Themechatherefore, is operative when energized to reduce the degree ofbrake application which it is possible to effect, or, in some instancesto increase the permissible degree of brake appli cation.

As the equipment must operate on the closed 40 circuit principle, thatis, as it is energized when the permissible degree of brake applicationis reduced to the minimum, it is essential to provide means to insurethat the equipment will be energized when the train is standing still or45 is moving at very slow speeds.

It is an object of my invention to provide an electrical speedresponsive apparatus operating on he closed circuit principle, that is,apparatus which is energized when it is desired to change 50 thepermissible brake application from some predetermined value.

A further object of my invention is to provide apparatus of the typedescribed which is reliable and accurate in operation, and which willre- 55 spond uniformly to changes in vehicle speeds whether the vehicleis accelerating or deceleratmg.

Another object of my invention is to provide improved electrical speedresponsive mechanism capable of giving a different response to each of aplurality of different changes in the vehicle speed.

Certain types of railway vehicles, such as locomotives, are equippedwith vehicle carried signal apparatus which is selectively responsive todifferent current impulses transmitted through the track rails orotherwise to inform the engineman of traflic conditions in advance. Ithas heretofore been proposed to also equip such vehicles with speedresponsive mechanism, together with means for controlling the vehiclebrake equipment or the motive power, or both, and to have this meanscontrolled by the speed responsive mechanism and the vehicle carriedsignal apparatus in such a manner that the brakes will be automaticallyapplied or the motive power cut-01f, or both, in the event that thevehicle is operated at a speed in excess of that permitted for existingtrafiic conditions as indicated by the vehicle carried signal mechanism.

It is an object of my invention to provide improved speed responsivemechanism adapted for use in an installation of the type describedabove.

A further object of my ilnvention is to provide an improved speedresponsive mechanism adapted for use in connection with vehicle carriedsignal apparatus and arranged to provide a plurality of differentcut-off or control speeds with a minimum of apparatus.

Another object of my invention is to provide improved speed responsivemechanism incorporating means for detecting wheel sliding as a result ofbrake applications.

A further object of my invention is to provide improved speed responsivemechanism of the type described which is normally responsive to rotationof a primary axle, but which is automatically placed under the controlof a different axle in the event that rotation of the primary axleceases because of too heavy brake applications and resultant wheelsliding.

Another object of my invention is to provide improved vehicle carriedspeed responsive mech anism which cooperates with vehicle carried signalmechanism to provide a warning indication if the permissible speedlimit, as determined by the signal mechanism, is approached, and which,if this speed limit is exceeded, will give a warning alarm, and willthereafter effect an application of the brakes if the vehicle speed isnot reduced below the permissible speed limit within a predeterminedtime.

Other objects of my invention and features of novelty will be apparentfrom the following description taken in connection with the accompanyingdrawings in which Fig. 1 is a diagram showing one form of speedresponsive apparatus embodying my invention as applied to a vehicle forvarying the braking power of the brake equipment of such vehicle inaccordance with the vehicle speed,

Figs. 1A and 1B are fragmentary diagrammatic views illustratingmodifications of the apparatus' shown in Fig. 1 which I may employ,

Fig. 2 is a diagram showing a modified form of apparatus,

Fig. 2A is a fragmentary diagram showing a modification of the systemshown in Fig. 2 which I may employ,

Fig. 3 is a diagram showing speed responsive mechanism embodying myinvention and cooperating with vehicle carried signal apparatus toprovide a plurality of permissive speed limits in accordance withtraffic conditions in advance, and

Figs. 4 and 5 are diagrams showing modified forms of systems embodyingthe invention.

The speed responsive mechanism shown in Fig. 1 of the drawings hasassociated therewith magnet valve devices L, M and H which areincorporated in the vehicle brake system, not shown. This brake systemmay be of any suitable well-known type, and one form of system which Imay employ is shown in United States Patent No. 2,095,505 to George W.Baughman.

The brake equipment with which the speed responsive mechanism shown inFig. l of the drawings is employed is capable of developing sufficientforce to press the brake shoes against the wheels firmly enough toproduce a predetermined rate of retardation of the train when the trainis traveling at a relatively high speed. When the low speed magnet L isenergized, and the magnets M and H are both deenergized, the brakingequipment is conditioned to be able only to develop substantially lessthan the full braking power, the braking force being limited to a valuesuitable for use when the train is traveling at a relatively slow speed,such as below 30 miles per hour.

The brake equipment is also arranged so that when the medium speedmagnet M is energized, at which time both the low speed magnet L and thehigh speed magnet H are both deenergized, the brake equipment isconditioned to permit a higher degree of braking force to be developedthan is obtainable when the low speed magnet L is energized. The brakingforce permitted when the magnet M is energized is suitable for use whenthe train is traveling at a medium speed, such as in excess of 30 milesper hour, but below 60 miles per hour.

Similarly, the brake equipment is arranged so that when the high speedmagnet H is energized, at which time the magnets M and L are bothdeenergizecl, the brake equipment is conditioned to permit the maximumbraking force to be developed to thereby produce braking power suitablefor use when the train is traveling at rela tively high speeds, such asin excess of 60 miles per hour.

The details of construction of the brake equipment are not a part ofthis invention, and the brake equipment, therefore, is not shown in de--tail in this application. Similarly, the invention is not limited to theparticular arrangement of speed control magnets shown, and it iscontemplated that one or more of these magnets may be operative whendeenergized to condition the brake equipment for service in a particularrange of train speeds, and to be inoperative when energized to conditionthe equipment for this" class of service.

Referring next to Fig. l of the drawings, the reference character I00designates a movable contact of the make-before break type which isactuated by cam IOI secured to an axle I of a vehicle to the speed ofwhich the system is intended to respond. When the vehicle is moving thecontact I 00 alternately engages fixed contacts I02 and I03 to controlthe supply of current to wires I04 and I05.

While the contact I00 has been shown as a movable contact actuated by acam mounted on the vehicle axle, the invention is not limited to the useof this construction, and other suitable forms of contact structure maybe employed. Thus the axle may have mounted thereon a commutator havingtwo segments, one of which is connected to one terminal of the source ofelec tric energy. This commutator may have associated therewith a pairof brushes which are so arranged and proportioned that one or the otherof these brushes willbe in engagement with the energized one of thecommutator segments at all times.

For controlling the brake magnets L, M and H, I provide a low speedrelay KL having three windings I06, I07 and I08, and a high speed relayKH having two windings I09 and H0. For controlling the relays KL and KH,I provide a low speed polarized relay JL having two operating windings IH and I I2, and a high speed polarized relay JH'having two operatingwindings H3 and The windings III and H2 are wound so that when windingII! is energized, contact I25 of relay JL is caused to assume itsleft-hand position as q shown, and when winding H2 is energized, contactI26 is caused to assume its right-hand position. In a similar mannerwindings H3 and H t of relay JH are wound so that its contact I32 iscaused to assume a left-hand or a right-hand position according aswinding l I3 or Il'i, respec tively, is energized.

The relays JL and JH are provided with short circuit'ed windings 89 and96], respectively, which operate in the well-known manner to retardresponse of therelays to changes in the energiza-- tion of the windingsthereof, and thereby prove the cut-off action of the relays at thecritical vehicle speeds. I

The system shown in Fig; l of the drawings includes zero-speed relays A!and A2 which provide means to maintain the supply of current to thewindings I! and I93 of the low speed relay KL, and thereby maintain thecontacts of relay KL picked up at times when the axle I is not rotatingor is turning at relatively slow speeds.

, When the vehicle is in motion, the first operation of contact Illll(assuming this to be the closing of contact Hill-I62) causes the windingof relay AI to beenergized by a circuit which. may be traced over a pathwhich passes from terminal 26 through contact Illl-lll2,wire I05, wireI3ll,back contact II! of relay AZ, and winding of relay Al to terminalC. Upon the second operation of contact I08, that is the closing ofcontact IMII!3 and the opening of contact Hill-4M, relay AI be comesreleased, and the winding of relay A2 be-- comes energized by a circuitwhich may be traced over a path which passes from terminal B throughcontact Hill- W3, wire IM, wire I l8, back contact i ll! of relay AI,and winding of relay A2 to terminal C. Thus the contacts of relays Aland A2 become alternately picked up and released at a speedcorresponding to the speed of rotation of axle I. Furthermore, sincecontact Illll is oi the make-before-break type, one or the other ofrelays AI or A2 will be energized when the ve-,

hicleis at rest.

As here shown, the winding of relay AI is energized and that of relay A2is deenergized with the result that winding I68 of low speed relay KL isenergized by a circuit which may be traced from terminal B throughcontact Hillilli, wire H35, wire I30, back contact I I! of relay A2,front contact I of relay AI ,and winding Illt to terminal 75, C. If thevehicle should stop with contact the pick-up time of relay A2.

IUD-403 closed, then the winding of relay A2 would be energized andthatoi relay AI would be deenergized with the result that winding I01 ofrelay KL would be energized by a circuit which may be traced fromterminal 13 through contact NHL-I03, wire I04, wire '8, back contact H9of relay AI front contact IZI of relay A2, and winding II" to terminalC. It will be plain that withv the vehicle at rest as shown in thedrawings, a winding of relay KL will be energized to close vehicle toprovide the degree of braking power appropriate for low vehicle speeds.

On rotation of the axle I and the cam IllI, the movable contact Hill isoscillated between the positions in which it engages the contacts I02and 5513. With the equipment in the position shown in Fig. 1 of thedrawings, the contact IllIl establishes a circuit from terminal B to thewire I025 from which a circuit is established by way of the wire I andcontact II"! of relay A2 to the winding of relay AI and energizes thiswinding. Contact I29 of relay AI accordingly is picked up with theresult that current is supplied from wire I05 to the winding Illa ofrelay KL toenergize that winding.

, On rotation of the axle I and the cam IUI, the contact I60 moves to aposition in which it no longer establishes the circuit from the terminalB to the wire 05 and in which the contact 100 connects the terminal B tothe wire I94. As soon as the connection between the terminal B and thewire I=l5 is broken by the contact Hill, the circuit through the windingI03 of relay KL and through the winding of relay AI is interrupted.

The connection from terminal B to wire lM is established by the contactIllfl before the circult to the wire IE5 is interrupted. However, thecircuit from wire I04 to the winding of relay A2 is not completed untilthe contact IIS of relay AI is released, which does not occur until asmall time interval after the interruption of the supply of current tothe winding of relay Al. Furthermore, a. circuit is not established fromthe wire Hi4 to the winding Ill! of the relay KL until the contact I2!of relay A2 is picked up, which does not occur for a small time intervalafter the circult to the winding of relay A2 completed by the release ofthe contact I I ll of relay AI.

It will be seen, therefore, that on movement of the contact Hill out ofengagement with the contact H32. and into engagement with the contactI63, the winding I68 of the relay KL is cleanergizec as soon as thecontact lit) becomes disen gaged from the contact I92, but that thewinding I9! does not become energized until a brief time intervalafterwards. This time interval is determined by the release time ofrelay AI and by remains substantially uniform. at all times,-and is notaffected by changes in the rate of rotation of the axle, andaccordinglyof the speed of the train with which the equipment isassociated. This time interval in which neither of the wind- This timeinterval.

ings I01 and I08 of relay KL is energized is only of such duration,however, that the contacts of the relay KL, if picked up, will remainpicked up untilone. of the windings is again energized.

As the axle I and the cam IOI continue to revolve, the contact I 00 willbe moved into engagement with the contact I02. When the contact I00engages the contact I02 it establishes a circuit from terminal B to thewire I65, but at this time the circuits from wire I05 to the winding ofrelay AI and to the winding W0 of relay KL are not complete because thewinding of relay A2 is energized and its contact II? is open. Ondisengagement of contact I00 from contact I03, the circuit to the wireI04 is interrupted, thereby interrupting the supply of current to thewinding of relay A2 and to the winding I0l' of relay KL.

Although the circuit from terminal B to wire I05 is established beforethe circuit to the wire I04 is interrupted, the circuits from the wireI05 to the winding of relay AI and to the winding I00 of relay KL arenot established for a time interval after the circuit to the wire ltd isinterrupted by the contact I00. When the contact I00 breaks the circuitto the wire I04, the supply of current to the winding of relay A2 isinterrupted and this relay thereupon releases after a small time delayknown as the release time or the relay. When the relay A2 becomesreleased, its contact III establishes a circuit from the wire I05 to thewinding of the relay AI, and after a time interval the contact I20 ofrelay AI is picked up and completes a circuit from wire I05 to thewinding I08 of relay KL.

It will be seen, therefore, that on movement of the contact I00 outofengagement with the contact I03 and the accompanying interruption ofthe supply of current to the winding I01 of relay KL, the winding I08will not become energized until after a time interval determined by therelease time of relay A2 and the pick-up time of relay Ai. As previouslystated, the time interval during which neither winding l0! nor winding38 is energized is only of such duration that during movement of thevehicle at extremely slow speeds the contacts of the relay KL willremain picked up until one of the windings is again energized.

0n continued rotation of the axle I and the cam IN, the cycle ofoperations described above is repeated, the windings of relays AI and A2being alternately energized, while the windings I01 and I08 of the relayKL are alternately energized, there being intermediate periods in whichI neither winding is energized, the length of these intermediate periodsbeing determined by the release and pick-up times of relays Al and A2.

The duration of the periods in which a cir cuit is established fromterminal B to each of the wires I04 and I05, and similarly the timeintervals between disengagement of movable contact I00 from one of thestationary contacts, and from the other of the stationary contacts,varies in accordance with the speed of rotation of the axle I, tneseperiods being relatively long when the axle is rotating at a slow speed,and being relatively short when the axle is rotating at a high speed.

As previously pointed out, there is a substantially constant timeinterval from the time at which the circuit to either of the wires I0 2and I05, and therefore to one of the windings of the relay KL, isinterrupted, and the time at which the supply of current is establishedto the other of the windings of the relay KL. This constant timeinterval in which neither winding of relay KL is energized issubstantially shorter than the periods between interruptions in thecircuits from terminal B to the wires I04 and 505 when the axle I isrevolving at a very slow speed. Accordingly when the axle I is rotatingat a very slow speed, after each interruption in the circuit to one ofthe wires I04 or I05, there will be the previously mentioned constanttime interval in which neither winding of the relay KL is energized,while this time interval will be followed by a period in which currentis supplied to one of the windings of the relay 1a.. As the axle isassumed to be rotating at a very slow speed, the intervals betweeninterruptions the circuits to the wires I04 and I05 will be relativelylong, and after each such interruption, the substantial time intervalmentioned above must elapse during which current is not supplied toeither of the windings of the relay KL. The portion of the total elapsedtime in which current is supplied to one or the other of the windings ofthe relay KL is such, however, during rotation of the axle at very lowspeeds, that the contacts of the relay KL will be picked up and willremain picked up.

As the speed of rotation of the axle increases, the duration of theintervals between interruptions in the circuits from terminal B to thewires IM and I05 decreases, and since the duration of the periodsfollowing each interruption in which no current is supplied to thewindings of the relay KL is unafiected by the change in the rate ofrotation of the axle, the duration of the time intervals remaining afterthese periods and in which current is supplied to the windings of therelay KL gradually decreases with the result that with an increase inthe vehicle speed, the portion of the total elapsed time in whichcurrent is supplied to the windings of relay KL progressively decreases.

When the rate of rotation of the axle has increased to a predeterminedrelatively low value, such as the rate corresponding to a vehicle speedof 5 miles per hour or even less, the portion of the total elapsed timein which current is supplied'to the windings I01 and I00 of the relay KLis reduced to such an extent that the degree of energization of thewindings of relay KL is insuflicient to hold the relay contacts pickedup. ..s the rate of rotation of the axle I increases to an even highervalue, the degree of energization of the windings I01 and I08 of relayKL is further reduced and is reduced to such an extent that the forceexerted by these windings to hold the relay contacts picked up isnegligible. The contacts of relay KL are thereafter entirely under thecontrol of the winding I03, the supply of current to which is controlledby the relay JL.

Vfhen the vehicle is in motion so that the axle l is rotated and thecontact I 00 is oscillated between its two positions, circuits arealternately established to the wires I04 and I05 with the result thatwindings III and I52 of relay JL are alternately energized to cause itscontact I26 to operate between its extreme right-hand and left-handpositions. Similarly the windings II 3 and H0 of relay JI-I arealternately energized to cause the contact I32 of that relay to operatebetween its extreme right-hand and left-hand positions.

When the axle I is rotating so that the con tact I00 is operated betweenits two positions, the two end portions of primary winding I 29 oftransformer I28 are alternately energized in opposite directionssimultaneously with the energization of windings III and'II2 of relayJL, while contact I26 of relay JL rectifies the current of thetransformer secondary winding I21 sufficiently to cause current of onerelative polarity to be predominant in the current supplied to windingI06 of relay KL from the secondary winding I2! of transformer I28. Thecircuit for energizing winding III and the right-hand portion of primarywinding I29 may be traced from terminal B through contact HID-I02, wireI05, wire I30, Winding III of relay JL, and right-hand portion ofsecondary windingIZS to terminal C.

The circuit for energizing winding N2 of relay JL and left-hand portionof primary winding I29 of transformer I28 may be traced from terminal Bthrough contact |0!!I03,,wire I04, wire II6, winding H2, and left-handportion of winding I29 to terminal C.

Similarly, the left-hand and right-hand portions of the primary windingI34 of transformer I33 are alternately energized in opposite directionssimultaneously with energization of windings H3 and II 4 of relay JH,while the contact I32 of this relay causes rectified current to besupplied from the secondary winding I35 of transformer I33 to thewinding I09 of relay The circuits through which current is supplied tothe windings III; and II of relay JH and to primary winding I3 3 oftransformer I33 are similar to the circuits traced in detailinconnection with relay JH and transformer I28.

Condensers 4-3 and are connected across the transformer primary windingsI28 and I34, respectively, in order to'reduce the arcing at contactsHill-402 and Hill-Hi3.

Operation of the system shown in Fig. 1 of the drawings When the vehicleis moving at a speed of less than BGmiles per hour, the frequency of there versals in the periodic energization of windings III and H2 are suchthat contact I26 of relay JL is capable of following these reversals inenergization and effects the supply of substantially unidirectionalcurrent to winding I05 of relay KL.

The force exerted by winding I06 of relay KL when energized withrectified current supplied over contact Iii; supplements and assists theforce exertedby the windings Idl and I08 of relay KL. Upon an increasein the vehicle speed, however, to. some value above 30 miles per hourbutbelow miles per hour, for reasons hereinafter explained in detail, relayJ'L will cease operation so that contact I22 of relay KL becomesreleased, thereby interrupting the circuit to the winding IIil of relayKH and thus placing the high speed relay KH entirely under the controlof polarized relay JH. Relay JH, however, continues to be operative atthis vehicle speed with the result that its contact I32 alternatelyengages its righthand and left-hand fixed contacts to supply rectifiedcurrent from transformer I33 to winding I08 of relay KH to maintain thecontact I23 of relay KB. picked up. The force exerted by winding I09 ofrelay KH, when energized by rectified current supplied over contact I32supplements and assists the force exerted by winding I Iii.

It will be seen that the windings I I I and I I2 of relay JL areenergized in series with portions of the primary winding I20 of thetransformer I28. On each transfer in energization from one winding tothe other of the relay JL there is a reversal in the direction of flowof current in the primary winding I29 of the transformer I28, and acorresponding reversal of the flux in the iron of the transformer core.

As the speed of the train increases the frequency of the operations ofcontact IBB increases, and there is a corresponding increase in the rateof alternate energi'zations. of wires I04 and I05 and, therefore, in thereversals in the direction of flow of current through the transformerprimary winding. With this increase in the frequency of reversals of theflow of current through the primary winding of transformer I28, and inthe rate of the reversals in the flux in the transformer core, there isan increase in the impedance primary winding portions, and acorresponding decrease in the flow of current through these windingportions, and also through the windings I ii and N2 of relay JL, whichare connects in series with the portions of the transformer primarywinding.

When the speed of rotation of the axle I is increased to a predeterminedvalue, such as a rate corresponding to a vehicle speed in excess of 30miles an hour, the reversals in current flow through the transformerprimary winding I29 are increased to such a degree that the impedance ofthe winding builds up to a value such that too little current flows inthe circuits of the transiormer primary winding portions and therefore,in the windings of the relay JL to operate the movable contact I23 ofthe relay JL. This contact thereafter remains in its last operatedposition and, does not rectify the current supplied from the transformersecondary winding I21 to the winding we of relay KL. The winding I06 ofrelay KL thereafter is energized with alternating current and no longerassists in maintaining the relay contacts picked up.

On the increase in the impedance of the primary winding of thetransformer I28, and the corresponding decrease in the magnitude of thecurrent flowing in the circuit of the primary winding, there may be somereduction in the mag nitude of the current induced in the transformersecondary winding, and therefore in the current supplied from thetransformer secondary winding I21 to the winding I06 of the relay KL.The operating characteristics of the relay KL, however, are such thatthe contacts of the relay will both pick up and remain picked up whenthe current supplied to its winding I06 is at the value which is presentat the time that the flow of current through the transformer primarywinding portions and the windings III and II2 of the relay JL'becomesinsufficient to effect operation of the movable contact fore, until therelay JL becomes inoperative, whereupon the winding I05 of relay KL willno longer be supplied with rectified current and the contacts of relayKL will be released.

As previously pointed out, on an increase in the rate of rotation of theaxle I there is a reduction in the portion of the total elapsed time inwhich current is supplied to the windings I01 and I08 of the relay KL,thereby weakening the force created by these windings and tending tohold the contacts of relay KL picked up. The values of the various partsof the system are arranged and proportioned so that the current suppliedto the windings I01 and I08 will be sufficient when the axle is rotatingat relatively low speeds, such as rates corresponding to vehicle speedsof 5 miles per hour or less, to keep the contacts of relay KL picked up.When the rate of rotation of the axle exceeds this value, the currentsupplied to the I26 of relay JL. The contacts of relay KL will remainpicked up, there-' windings I61 and I88 is so greatly diminished thatthese windings do not exert substantial force tending to maintain therelay contacts picked up.

As soon as the axle starts to rotate, however, circuits are periodicallyestablished to the wires I04 and I05, and therefrom to the primarywinding I29 of the transformer I28, and accordingly rectified current issupplied from the transformer secondary winding to the winding I06 ofthe relay KL. At very slow speeds of the axle I the impulses of currentin the circuit of the wires I04 and I05, and therefore in the windingsIII and I I2 of relay JL and the portions of primary winding oftransformer I28, are relatively infrequent with the result that theimpulses of current supplied to the winding I06 of the relay KL arerelatively infrequent, and little force is created by the winding I06tending to hold the relay contacts picked up. As the rate of rotation ofthe axle I increases, the frequency of the impulses of current to thewinding I06 of relay KL increases, and increases the force created bythis winding tending to hold the relay contacts picked up.

The various parts of the system are arranged and proportioned so that onan increase in the rate of rotation of the axle I, the value of thecurrent supplied to the winding I66 increases rapidly enough tocompensate for the decrease in the value of the current supplied to thewindings I01 and I08. Accordingly, as the force exerted by the windingsl0! and I08 diminishes, the force exerted by the winding I I36increases, with the result that the contacts of relay KL are maintainedpicked up throughout the increase in the rate of rotation of the axle Ifrom zero speed to a rate in excess of that at which the windings IE3!and 28 are ineffective to hold the contacts of relay KL picked up.

As the rate of rotation of the axle I increases further, the frequencyof the impulses of current supplied to the primary of the transformerI28 increases to a degree such that the impedance of the transformerwinding reduces the flow of current through the circuits of thetransformer primary winding portions and the windings III and I I2 ofrelay JL, as explained in detail above. When the rate of rotation of theaxle I reaches a predetermined value, such as the rate corresponding toa vehicle speed of 30 miles an hour, the current flowing in the windingsof relay JL is insufiicient to effect operation of the movable contactof this relay, and this contact will no longer rectify the currentsupplied from the transformer secondary winding 'to the winding I06 ofrelay KL and the contacts of relay KL are thereupon released, as haspreviously been explained.

When contact I23 of relay KH is picked up and contact I24 of relay KL isreleased, a circuit is established for the medium speed brake magnet Mso that the braking system of the vehicle is conditioned to providemedium speed braking power. The circuit for magnet M is traced fromterminal B through front point of contact I23 of relay KH, back point ofcontact I24 of relay KL, and magnet M to terminal C.

As previously mentioned, when the contacts of relay KL become released,the circuit for supplying current to the winding H0 of relay KH isinterrupted, thereby placing contact I23 of relay KH entirely under thecontrol of winding I09, which at this time is supplied with rectifiedcurrent from the secondary winding I 35 of transformer I33.

The relay JH and the transformer I33 are chosen so that their operatingcharacteristics are such that when the vehicle speed is below apredetermined relatively high speed, such as 60 miles an hour, thecurrent flowing in the circuits of the windings I I3 and N4 of the relayJH and the primary winding I34 of the transformer I33 will be sufficientto cause operation of the contact I 32 of the relay JH. The relay JH andthe transformer I33 are also chosen so that their op eratingcharacteristics are such that when the vehicle speed exceeds thispredetermined relatively high rate, because of the increase in theimpedance of the transformer primary winding It l, the current flowingin the windings H3 and II l of the relay JH will be so greatly reducedas to be insufficient to cause operation of the contact I32 of relayJI-I. This contact will thereafter remain in its last operated positionand will not rectify the current supplied from the transformer secondarywinding I35 to the winding Illfi of relay Kl-I. The contact I23 of relayKH will thereupon be released.

On the reduction in current flow in the circuits of the windings IIS andH4 of the relay JH, and in the primary winding I 34 of transformer I33,caused by the increase in the impedance of the transformer winding,there may be a reduction in the magnitude of the current induced in thetransformer secondary winding, and therefore in the value of the currentsupplied from the transformer secondary winding to the Winding H39 ofthe relay KI-I.

The relay KH and the other portions of the system are arranged andproportioned, however, so that the contacts of relay KI-I will both pickup and remain picked up until the current in winding it!) is reduced toan even lower value than that which is present when the relay JH becomesinoperative. The contact I23 of relay KH, therefore, will remain pickedup until the relay JH becomes inoperative, whereupon the contact ofrelay KH becomes released and interrupts the circuit of the medium speedmagnet M. The releasing of the contact of relay KI-I causes it to engageits back point of contact I23 to energize the high speed magnet H tocondition the braking apparatus to provide the high speed braking power.

Modification shown in Fig. 1A of the drawings If desired, the controlfor windings III and I I2 of relays JL and JH may be modified as shownin Fig. 1A. In this modification, the circuit for winding II of relay JLincludes a back contact I3! of relay A2, and the circuit for winding II2includes a back contact I38 of relay AI.

Thus it will be seen that an engagement of contact I!!!) with contactI03, a circuit is established to wire I04 and thus to wire I30, but thata circuit is not immediately completed through winding H2 of relay JL asis done in the system shown in Fig. 1. Instead the supply of current towinding i2 of relay JL is delayed until relay Al becomes released. RelayAI will not become released for a brief time interval after the circuitto wire I05, and therefore to the wire HE is interrupted, which will notoccur for a brief time interval after the circuit to wire I04 iscompleted.

Similarly, on movement of contact I00 into engagement with contact I62,a circuit is completed to wire I65 and wire I IE, but the circuit fromwire H6 through winding III of relay JL is not completed until the relayA2 becomes released, which will not occur for a brief time intervalafter the circuit to wire I04 is interrupted.

On each oscillation of contact I00, there is a brief time interval inwhich neither winding Ill nor winding N2 of relay JL is energized. Thistime interval is determined by the release times of relays A! and Alland is not affected by changes in the rate of rotation of the axle I.However, as previously pointed out in connection with the supply ofcurrent to the windings I01 and ms of the relay KL, on an increase inthe rate of rotation of the axle l, the portion of the total elapsedtime in which current is supplied to the windings Hi and N2 of relay JLgradually decreases.

It will be seen that with the arrangement shown in Fig. 1A, on anincrease in the rate of rotation of the axle I, there is a reduction inthe degree of energization of the windings of the relay JL for tworeasons. One cause of the reduction in the degree of energization orthese windings is the gradually reduced portion of the total time inwhich current is supplied to these windings, while the other cause ofthe reduction in the degree of energization of the windings of the relayJL is the reduction in the flow of current through the primary windingof the transformer associated with the relay occasioned by the increasein impedance on the increase in the frequency of the reversals in theflow of current in the transformer primary winding.

As two diil'erent forces are operative to reduce the degree ofenergization of the windings of relay JL in the system shown in lA, the,degree of energization of these windings will be reduced more ly thanit is reduced in the system shown in. Fig. l, in which only a singleforce is operative to reduce the degree of energisation of the windin sof the relay JL. It has been found that the rapid reduction in thedegree of energization of the windings of relay JL provided by thesystem shown in Fig. 1A results in a sharper and more clearly definedcut-off point for the relay. Furthermore, the arrangement shown in iAprovides some protection against variations in the outwit value oi therelay JL due to increases in voltage for the reason that any increase involtage supplied to relays Al or tends to maintain the back contacts ofthese relays open for a greater period; thus still further reduce theperiod of energization of windings Ill and H2.

While the modification shown in 1A has been illustrated and described inconnection with the relay JL, it is obvious that the supply of currentto the windings of the relay JH may be controlled-in the same manner.

Modification shown in Fig. 1B of the drawings In Fig. 1B there is showna modified form of circuit arrangement which I may employ to effectenergization of a winding of the relay Kilo by current supplied by thezero-speed relays Al and A2. In the system shown in 1B the relay KLo isprovided with only two windings, while current is suppli d to the one ofthese windings by both of the zero-speed relays.

In the operation of this modification, on completion of the circuit tothe wire lit at a time when wire ill: is deenergised, a circuit i."established through contact ill of relay A2 to ener" gize the winding ofrelay Al. When contact iilil of A! becomes picked up, a circuit isestablished through contact to wire lit-a leading to the winding lfi'iaof relay KL.

Similarly, when a circuit is established to wire H8 at a time when 'wireH6 is deenergized, a circuit is completed through contact N9 of relay Alto the winding of relay A2, while as soon as the contact l2! of relay A2becomes picked up, a circuit is completed from wire i'ill throughcontact l2! of relay A2 to wire (Zoo. to winding 181a of relay KL.

The ratio of the time during which current is supplied to the windingIdle to the total elapsed time gradually decreases in the mannerdescribed in detail in connection with Fig. 1 when the frequency of theinterruptions inthe establishment of circuits to the wires Hi3 and litis increased. qt extremely low vehicle speeds the winding lll'la isenergized a suiiiciently large portion of the time to keep thecontactsof relay KL-a picked up, but when the vehicle speed is increased to arelatively low value, in excess of five miles per hour, the time ofenergization of the winding lll'la is reduced to such an winding is nolonger eflective to keep the relay contact picked up.

Construction of system shown in 2 of the drawings Referring next to Fig.2, I have provided a medium speed control relayKM in addition to the lowspeed control relay KL and the high speed control relayKl-I. I have alsoprovided a super high speed brake control magnet SE in addition to theother bra--e control magnets L, M and H.

When relays KL, KM and K1 2 are all energized, a circuit is closed forlow speed brake magnet L so that the normal braking power of the vehiclebrake equipment is effective. This circuit is traced from terminal Bthrough front point of contact l5il of relay KH, front point of contactHit of relay KM, and front point of contact 552 of relay KL.

When low speed relay KL deenergized and relays and KH are bothenergized, a circuit is established for medium speed brake magnet M, awhich circuit is traced from terminal B through front point of contactEll of relay KH, front point of contact back point of contact of relayKL.

Vihen relay KM is deenergized and relay Kll is energized, a circuit isestablished for high speed brake control magnet H which circuit istraced from terminal B through front point of contact loll of relay backpoint of contact l5! of relay KM, and magnet H to terminal 0.

. When relay Kl-l is released, a circuit is established for the superhigh speed magnet SH which circuit is traced from terminal through backpoint of contact iii-t! oi? relay Iii-I and magnet SH to terminal C.

Thus, it will be seen that brake control magnets L, M, H and SH may beselectively controlled in accordance with the condition of relays KL, KMand KH. The brake control magnets L, M and El will ordinarily beutilized to vary the braking power of the vehicle brake equipment in amanner similar to that described for the apparatus shown in the Fig. l,and magnet SH when energized will usually be effective to condition thebraking system to provide the maximum braking power.

Relay KL is controlled by contact Hi6, zerospeed relays Al A2, relay JLand transformer 128 in manner identical to that described for thecorresponding apparatus in Fig. 1. That is, windings ill"! and oi relayKL are provided to maintain the contacts of relay KL picked up m ofrelay KM, and

extent that this when the vehicle is at rest or is moving at very slowspeeds, and the winding I06 of relay KL is controlled by contact I26 ofrelay JL and transformer I28 to maintain the relay KL in its energizedcondition when the vehicle is traveling below the speed of approximately30 miles per hour. When relay KL is energized, energy is supplied overits front contact I53 to winding I54 of relay KM, and winding I55 ofrelay KH, in series to maintain relays KM and Ki! in their energizedcondition.

For controlling the relay KI-I, I provide the high speed polarized relayJ H, and for controlling the relay KM, I provide a medium speedpolarized relay JM. For governing the relay JM, I provide a pair ofcounting or stepping relays CI and C2, and for controlling the relay JH,I provide a group of counting relays EI, E2, E3 and E4.

Relays CI and C2 are controlled by each other and by contact I60 whichis actuated by cam I6I on axle I in such a manner that these relays makea complete cycle of operation once in every two revolutions of axle l'.

Relays E1, E2, E3 and E4 are controlled, by contact I60 and by eachother in such manner that these relays go through a complete cycle ofoperation once in every four revolutions of the axle I.

Thus, it will be seen that the relays CI and C2 act as a speed reducingmechanism which, as will be explained more in detail hereinafter,provides for alternate energization of windings I62 and I63 of relay JMat a frequency which is proportional to the speed of operation ofcontact I60, but at a lower rate.

Likewise the counting relays El, E2, E3 and E4 act as a speed reducingmechanism for alternately energizing windings I64 and I65 at a frequencycorresponding to the speed of operation of contact I60, but at a stillfurther'reduced rate.

The contact I60 differs from the contact I00 as the contact I60 isarranged so that it will become disengaged from either of the stationarycontacts associated therewith before it engages the other stationarycontact. This is desirable because if the contact I60 were of themakebefore-break type, both stationary contacts would be engagedsimultaneously at times with the result that wires I61 and HI would bothbe energized, which might cause two or more of the groups of countingrelays to be energized simultaneously, thereby interfering with theintended operation of these relays.

The operation of relays CI and C2 is as follows: Upon the firstoperation of contact I60,

which is assumed to be closing of contact I60-- I66, winding I68 ofrelay CI is energized by a circuit which may be traced over a path fromterminal B through contact I60-I66, wire I61, upper winding I68 of relayCI, and back point of contact I69 of relay C2 to terminal C. Upon thesecond operation of contact I60, that is engagement of contacts I60-I10,a circuit is established for maintaining relay CI in its energizedcondition, and another circuit is also established for causing relay C2to assume its energized condition. The circuit for maintaining relay Clenergized is traced from terminal B through contact I60-I10, wire "I,lower winding I12 of relay CI, and front contact I13 of relay CI toterminal C. The circuit for energizing relay C2 may be traced over apath which passes from terminal B through contactv I60-I10, Wire I1I,lower winding I14 of relay C2, and front contact I15 of relay CI toterminal C.

Upon the third operation of contact I60 when contact I60-I10 becomesopen and I60-I66 becomes closed, energy is disconnected from lowerwinding I12 of relay CI to cause this relay to become released, and acircuit is established for relay C2 to maintain this relay in theenergized condition. The last named circuit is traced over a. path whichpasses from terminal B through contact I60-I66, wire I61, upper windingI16 of relay C2, and front point of contact I69 of relay C2 to terminalC. On this movement of contact I60 into engagement with contact I66 withthe resultant supply of energy to wire I61, the winding I68 of relay CIdoes not become energized because the contact I69 of relay C2 is pickedup, thereby interrupting the circuit through the winding I68 of relayCI. Accordingly, when the supply of current to the wire I1I isinterrupted on the third operation of contact I60, the relay CI becomesreleased and its contacts I13 and I15 are opened.

Upon the fifth operation of contact I60, that is, when contact I60-I66becomes open and contact I60-I10 becomes closed, the circuit throughwinding I16 of relay C2 is interrupted so that this relay will assumeits released condition.

On this movement of contact I60 into engagement with contact I10 withthe resultant completion of a circuit to wire I1I, the winding I12 ofrelay CI does not become energized since con tact I13 of relay CI isreleased, thereby interrupting the circuit through winding I12. Thecontacts of relay CI, therefore, remain released.

Similarly on this completion of the circuit to wire III, the winding I14of relay C2 does not become energized since contact I15 of relay CI isopen, thereby interrupting the circuit through the winding I14 of relayC2. As the circuit to wire I61, and therefore to winding I16 of relayC2, is interrupted on this operation of the contact I60, both windingsof relay C2 are deenergized, and the contact of this relay becomereleased.

Upon the fifth operation of contact I60, that is when contact I60-I66again becomes closed, which is the start of a new cycle, winding I68 ofrelay CI again becomes energized to initiate another cycle of operationsimilar to that just described for the first four operations of contactI60. The contact I60 makes two operations for each revolution of theaxle I, and since the contacts of relay CI become picked up and releasedonce for each four operations of contact I60, that is, once for each tworevolutions of axle I, it will be plain that contact I18 of relay CI maybe utilized to eifect the alternate energization of windings I62 and I63of relay JM, and of the right-hand and left-hand portions of the primarywinding of the transformer I91 associated with relay JM, at a frequencywhich will be exactly one-half the rate of operation of contact I60.

In addition, it will be seen that contact I18 of relay CI becomes pickedup on the first operation of contact I60, and remains picked up untilthe third operation of contact I60, whereupon the contact is releasedand remains released until the first operation of contact I60 in a newcycle of operation, with the result that the periods in which current issupplied to the windings I62 and I63 of relay JM are of substantiallyequal length.

Operation of the counting relays employed in the system shown in Fig. 2of the drawings The counting relays El, E2, E3 and E4 operate asfollows: Upon the first operation of contact I60, that is closing ofcontact I60-,-I.6,5,, Winding I of relay EI becomesenergized by acircuit which passes from terminal B through contact Hie-466, wire IISI,upper winding I80 of relay EI, and back point of contact I8I of relayEl.

Upon the second operation of contact which is closing of contactIBll-ITI'I, Winding I82 of relay E2 becomes energized by a circuit whichpasses from terminal B through contact I6 0--I I0, wire I1 I, upperwinding I32 of relay E2, and front contact I83 of relay EI to terminalCI. Relay EI is maintained in its energized condition even thoughcontact I80-I6B.becomes open because another circuit is established forrelay EI which circuit may be traced from terminal B through contactlull-I10, wire III, lower winding I84 of relay EI, and front contact I85of relay-El to terminal C. g

Upon the third operation of contact I60, that is, when a circuit isagain established to wire I61, upper winding I80 of relay EI is againenergized by the previously traced circuit for this winding, and windingI 85 of relay E3 becomes energized by a circuit which includes wireIS'I, upper winding I86 of relay E3, and front contact I81 of relay E2,the latter contact being maintained picked'up because the lower windingI88 of relayE2 receives energy from wire IB'I over a circuit whichincludes front contact I89 of relay E2.

Upon the fourth operation of contact I60, that is, when energy is againsupplied -to wire. II'I, lower winding I84 of relay EI and upper windingI82 of relay- E2 both receive energy over the previously traced circuitsto maintain these relays in their energized condition. Relay E3 is alsomaintained in its energized condition because its lower winding I90 isenergized by current from wire III through a circuit which includesfront contact I9I of relay E3. Upon this operation of contact I50, relayE4 becomes energized because its upper winding I92 receives energy froma circuit which includes wire I'II, upper winding I92 of relay E4 andfront contact I93 of relay Upon the fifth operation of contact I60, thatis, when a circuit is established to wire I91, relays E2 and E3 aremaintained in their energized condition because windings I88 and I86 ofthese relays respectively, are energized over their previously tracedcircuits. Relay E4 is also maintained in its energized condition by acircuit whichincludes Wire I01, lower winding I94 of relay E4 and frontpoint of contact I8I of relay E4. Upon this operation of contact I60,however, relay EI becomes released because the circuit for itsupperwinding I80 became opened by the opening of the back point ofcontact IBI of relay E4 which occurred when contact IBI was picked up onthe fourth operation of contact "I60.

Upon the sixth operation of contact I90, that is, when a circuit isestablished to wire Ill and the circuit to wire I6I'is interrupted,relay E2 becomes released because the circuit through its I winding I82is interrupted by the opening of contact I83 of relay EI, but relays E3and E4 remain energized because lower winding IQ!) of relay receivesenergy over a circuit which includes front contact IQI of relay E3,andupper winding I92 of relay E4 receives energy over a circuit whichincludes front contact I93 of relay E3.

Upon the seventh operation of contact I60, that is, when a circuit isestablished to wire I61 and the circuit to wire III is interrupted,relay E3 becomes released because its upper winding Idii is deenergizedas the circuit of this winding was interrupted by the opening of frontcontact I81 of relay E2, but e a E ain n its energized condition becauseits lower winding I9 is energized over front point of contact IOI ofrelay E4. Upon this operation of contact I60 to complete the circuit towire IS'I, the winding I80 of relay EI does not become energized becausethe contact I8I of relay E4 is picked up, thereby interruptijng thecircuit through the winding of relay EI.

Upon the eighth operation of contact I50, that is, when a circuit isagain completed to wire HI and the circuit to wire IIi'I is interrupted,relay Ed. becomes released because the circuit for its upper winding,I92 became interrupted by the opening of front contact I93 of relay E3.closing of back point of contact, ISI of relay E5 conditions the pick-upcircuit for upper Winding I80 of relay EI so that upon the ninthoperation of contact I60, that is the first operation in a new cycle of.operations, when a circuit is again completed to wire I61, the relay EIbecomes energized and a new cycle of operations of the count ing relaysEl, E2, E3 and E4 isinitiated.

From the foregoing description of the opera- I tion of the countingrelays, it is apparent that contact I96 of relay El picks up andreleases once for each eight operations of contact I130.

The

Fur-' thermore, it will be seen that the contacts of relay EI becomepicked upon the first operation ofcontact I60, andbecome released on thefifth 1 operation of contact I60 so that the periods in which the relayis energized and deenergizedare of substantially, equal duration.Contact I69 bein operated twice for' each revolution of axle i, itfollows that contact I96 of relay EI will pick up and release once foreach four revolutions of axle I. Thus, the alternate energizations ofwindings I64 and IB5of. relay JH, and of the right-hand and left-handportions of the primary winding of transformer I98 associated with relayJI-I, the circuits of, which arecontrolled by contact I96,

are made at a frequency corresponding to the speed of the vehicle, butat a rate which is still lower than the energizations of relay JM.

Therelay JM andfthe transformer I91 assoand adjustedthahwhenperiodically energized at ciated therewith may, for example, be sochosen a frequency corresponding to a vehicle speed of approximatelyGO'miles per hour, the flow of current in the relay-windings will be sogreatly reduced because of the impedance of the transformer winding thatcontact 200 of relay JM will become inoperative. Similarly, relay J Hand the transformer I98 associated therewith may,

for example, be so chosen and adjusted that, when periodically energizedat a frequency corresponding to speeds in excess of 90 miles per hour,contact 20I of relay JH will become inoperative. Operation of the systemshown in Fig. 2 of the I drawings As previously stated, the relay JL andthe transformer I28 associated, therewith are so chosen that whenperiodically energized at a frequencycorres'ponding to speeds in excessof 30 miles-an hour, contact 'I26 of relay'JL will be inoperative.

I shall first assume that the train is traveling at some slow speed say,for example, 20 miles per hour at which speed neither winding I01 norWinding I08 of relay KL will be supplied with sufficient energy by thezero-speed relays AI and A2, for reasons explained in detail inconnection with the system shown in Fig. 1, to maintain the contacts ofrelay- KL picked up with the result that the control of relay KL willdepend entirely upon the energy received through contact I26 of relay JLand transformer I28. In addition, during this movement of the train, theaxle I is 1'0- tated so that contact I60 alternately engages con,- tactsI66 and I10 with the result that the contact I18 of counting relay CI isperiodically operated, as described in detail above, to alternatelyenergize the windings I62 and I63 of relay JM and the two portions ofthe primary winding of transformer I91. 7

Similarly, the contact I96 of counting relay EI is operated toalternately energize the windings I64 and I65 of relay JH and theportions of the primary winding of transformer I98.

Since the contactsl18 and I96 of relays CI and EI are operated at ratesproportionately lower than the rate at which contact I60 is operated, atcomparatively low train speeds the impulses of current supplied by thecontacts I18 and I96 to the primary windings of transformers I91 and I96will be relatively infrequent. Accordingly, the impulses of currentsupplied from the secondary windings of transformers I91 and I98 to thewindings 202 and 203 of relays KM and KH, respectively, will berelatively infrequent, and at extremely low train speeds these impulsesof current to the windings 202 and 203 may be too infrequent to energizethese windings to a degree sufficient to cause these windings to holdthe contacts of the relays picked up. This is immaterial, however, asthe windings I54 and I of relays KM and KH are energized at this timethrough the circuit controlled by contact I53 of relay KL and operate tomaintain the relay contacts picked up.

When the speed of the vehicle is increased. to I some point above 30miles per hour, relay JL becomes inoperative, as described in detail inconnection with the system shown in Fig. 1, and the contact I26 nolonger rectifies the current supplied to winding I06 of relay KL.Accordingly the contacts of relay KL. are released and the medium speedmagnet M is effective to determine the condition of the braking systemof the vehicle, while windings I54 and I55 of relays KM and KH are bothdeenergized. The contacts of relays KM and KH do not, however, becomereleased on this deenergization of the relay windings I54 and I55because, in the meantime, the rate of operation of contact I18 of relayCI and contact I96 of relay EI, respectively, will have increased tosuch a degree that sufficient rectified current is supplied to upperwinding 202 of relay KM and to upper winding 203 of relay KI-I to renderthese windings effective to maintain the relay contacts picked up.

I shall next assume that the speed of the vehicle is increased to somevalue in excess of, miles per hour. Under this condition, the periodicenergization of windings I62 and I63 of relay JM will be of suchfrequency that the impedance of the primary winding of transformer I91will be high enough to reduce the current flow in the windings of relayJM to a value to render this relay inoperative. As a result, the contactI5I of relay KM will become released and will energize the high speedbrake control magnet H to condition the braking system for the highspeed braking power.

I shall next assume that the speed of the vehicle is increased to somespeed in excess of 90 miles per hour. Under this condition, theoperasult that contact I50 of relay KH will become released. Whencontact I50 of relay KH is released, the super high speed magnet HS willbe energized to condition the braking system for applying the brakingpower necessary at this high speed.

As the train speed reduces, relays JH, JM and JL will again becomeeffective to selectively control the brake governing magnets L, M, H andSH so that the braking system of the vehicle will be properlyconditioned in accordance with the speed of the vehicle.

Modification shown in Fig. 2A of the drawings If desired, windings I62and I63 of polarized relay JM may be controlled by contact 205 of relayE2 and contacts 206 and 201 of relay E4 as indicated in Fig. 2A. Thatis, relays CI and C2 can be dispensed with and windings I62 and I63 ofrelay JM controlled as follows: Starting with all the relays Edeenergized, at the start of the second period of operation of contactI60, relay E2 will be energized and its contact 205 will become pickedup with the result that during the periods following the second andthird operations of contact I60 Winding I63 of relay JM will receivecurrent through front point of contact 205 of relay E2 and back point ofcontact 206 of relay E4.

During the periods following the fourth and fifth operations of thecontact I60, the contacts of relay E4 are also picked up and winding I62of relay JM will receive current through front point of contact 205 ofrelay E2 and front point of contact 206 of relay E4.

During the periods following the sixth and seventh operations of contactI60, the contacts of relay E2 are released while the contacts of relayE4 remain picked up and winding I63 of relay J M will receive currentthrough back point of contact 205 of relay E2 and front point of contact201 of relay E4.

During the period following the eighth operation of contact I60 and theperiod following the first operation of contact I60 in the next cycle ofoperation, the contacts of relays E2 and E4 are released and winding I62of relay JM will receive current through the back point of contact 205of relay E2 and back point of contact 201 of relay E4.

From the foregoing explanation, it will be seen that in the system shownin Fig. 2A windings I62 and I 63 are alternately energized at a ratewhich is exactly twice the rate of energization of windings I64 and I65of relay JH. In other words, the rate of energization of windings I62and I63 with the arrangement shown in Fig. 2A will be the same as thatdescribed for the apparatus shown in Fig. 2.

While the modifications shown in Figs. 1A and 113 have beenv shown anddescribed in connection with the system shown in Fig. 1, it is to beunderstood that the system shown in Fig. 2 may be altered to includethese modifications if desired.

Thus the supply of current to the relay JL in the system shown in Fig. 2of the drawings may be controlled by the relays AI and A2 in the mannershown in Fig. 1A, while the relay KL employed in the systemv shown inFig. 2 may be provided with but two windings instead of three, and therelays Al and A2 arranged to supply current to the same one of thesewindings in the manner shown in Fig. 1B.

Construction of system shown in Fig. 3 of the drawings Referring to Fig.3 of the drawings, I have illustrated therein a modified form of speedresponsive mechanism embodying my invention. This form of speedresponsive mechanism is adapted for use on a vehicle equipped withsignal apparatus which is selectively responsive to dif ferent kinds ofcurrent "impulses transmitted through the track rails, or otherwise, inaccordance with traffic conditions in advance.

The mechanism shown in, this figure of the drawings includes a brakecontrol magnet valve device H which, when deenergized, effects an application of the brakes, while the speed responsive mechanism isarranged to maintain the magnet ,valve device I-I energized at all.times except is similar to that shown. in Fig. 2 and includes contacts220 andv 22,! which correspond to the contacts Hill and Hill of thesystem shown in Fig. 2, and are actuated by a suitable cam 22!! mountedon the vehicle axle 22.3.

The system shown in Figs. .3 of the drawings includes zero-speed relaysA i and A5, while italso includes a chain of four counting relays E5,E6. E1 and E8. This system also includes a control relay CR whichcontrols the brake magnet valve device Q, and a master relay MR, whichcontrols energization of a winding of the control relay CR.

The system employs, in addition, the train control relay TOR which formsa part of the train control or vehicle carried signal apparatus. Therelay TCR has a plurality of movable contacts which are movable to a.plurality of positions.

current of a different character, the relay contacts are caused tooccupy their left-hand or high speed positions, as shown in Fig. 3 ofthe drawings.

The details of the train control apparatus or vehicle carried signalmechanism which controls the supply of current to the winding'of therelay TOR forms no part of this invention, and any suitable apparatuswell-known in the railway signalling art may be employed for thispurpose.

The zero-speed relays A4 and A5 are provided for the purpose ofmaintaining a winding of the control relay CR energized when the vehicleis standing still or is moving at extremely low speed.

The zero-speed relays A4 A5 are controlled by the contact 220 in amanner similar to that described in detail in connection with the systemshown in Fig. 1 of the drawings.

The contact 220 is of the make-before-break type so that it is always inengagement with one or the other of the stationary contacts 225 and 226;The contact 225 is. connected by a wire 228 to a movable contact 229 ofrelay A5, while contact 225 is connected by a wire 230 to a movablecontact 231 of relayA4.

When the relay A5 is deenergized, as 'shown,

the contact 229 engages its back point of contact to establish a circuitfrom one terminal B of a suitable source of electric current throughcontacts 220 and 225, wire 228 to wire 232 which is connected toone-terminal of the winding of the relay A4. The other terminal of thewinding of the relay A4 is connected by a Wire 235 to the terminal atthe left-hand end of the primary Winding 23E of the transformer 23.8.The center tap of the primary winding 236 is connected to the otherterminal C of the same source of current as that to which the contact220 is connected.

When contact 220 engages contact 225 and relay A5 is deenergized,therefore, the winding of relay A l will be energized in series with theleft-hand former 238.

When the winding of relay A4 is energized, its

istics of which are hereinafter explained in detail,

to the terminal C of the same source of current as that to which thecontact 22!! is connected. Accordingly-when relay A4 is energized,current will be supplied to the winding 243 of relay CR by way of acircuit which includes the ballast lamp 245 in series.

In addition, at a time when the relay A4 is energized and the relay A5is -deenergized, the contact 2410f the relay A5 engages its back pointof contact to thereby connect the end terminal of the right-handportionof the secondary winding 24.9 of transformer 238 to a wire 25!] which isconnected to one terminal of the winding 252 of relay OR. The otherterminal of the winding 252 of relay GR is connected by a wire 253 to astationarycontact 2M associated with the train control relay TCR.

The contact 254 is engaged at certain times by a movable contact 255 ofthe relay TCR, while the movable contact 7355 is connected by a wire 251with the center tap of the secondary winding 24!] of transformer 238.-

Accordingly, at a time when the relay A5 is deenergized, current inducedin the right-hand portion of the transformer secondary winding 249 as aresult of the supply of current to and the interruption in the supply ofcurrent to the left-hand portion of the transformer primary winding 226will be supplied to the winding 252 of the relay CR providing themovable contact 255 of the train control. relay TCR is in its high speedposition as shown in Fig. 3 of the drawings.

When as a result of rotation of the axle 223,

the cam 222 is moved to a position to permit the movable contact 220 tomove into engagement with the stationary contact 26 and out ofengagement with'the contact 225, the relay A l hecomes deenergizedbecause of the interruption in the supply of current to its winding dueto winding of the relay A5 is connected by the wire 2 to the terminal atthe right-hand end of the primary winding 226 of transformer 238, whilethe center terminal of this winding is connected to the terminal C ofthe same source of current as that to which contact 220 is connected.

It Will be seen, therefore, that when contact 220 is out of engagementwith contact 225 and in engagement with contact 226, a circuit isestablished from terminal B through the winding of relay A5 and throughthe right-hand portion of the primary winding 226 of transformer 238 assoon as contact 23l of relayA4 engages its back point of contact.

On energization of the winding of relay A5, its contacts become pickedup, and when the movable contact 262 of relay A5 engages its front pointof contact, a circuit is established from wire 259 to wire 242 leadingto the winding 243 of relay CR, the other terminal of which is connectedin series with ballast lamp 245 to the terminal C of the source ofcurrent.

On energization of the winding of relay A5, its contact 241 becomespicked up, thereby interrupting the connection between the right-handend portion of secondary winding 249 of transformer 238 and the wire25!], while on deenergization of the winding of relay A4, its contact26l engages its back point of contact, thereby establishing a connectionfrom the left-hand end portion of the transformer secondary winding 249to the wire 250 with the result that current induced in the transformersecondary winding by current supplied through the contact 23l of relayA4 to the transformer primary winding will be supplied by way of thewire 250 to energize the winding 252 of relay CR.

On a subsequent operation of the contact 220 by the cam 22 so that thecontact 220 no longer engages the contact 226 and again engages thecontact 225, the relay A5 becomes deenergized due to the interruption inthe supply of current to its winding on movement of contact 220 out ofengagement with contact 226, and contact 241 of relay A5 establishes aconnection to permit the supply of current from the right-hand portionof transformer secondary winding 249 to the wire 250 and thereby to thewinding 252 of relay CR, while the relay A4 again becomes energized andeffects the supply of current to wire 242 leading to the winding 243 vofrelay CR.

As will be understood, the various portions of the primary and secondarywindings of the transformer 238 are arranged so that the currentsupplied from the secondary winding 249 to the wire 250, and thereby tothe winding 252 of relay CR, will always flow in the same direction andso that the direction of flow will be such that the force created onenergization of the winding 252 will assist the winding 243 inmaintaining the contacts of the relay CR picked up.

As explained in detail in connection with the system shown in Fig. 1 ofthe drawings, on each movement of contact 220 into engagement with onestationary contact and out of engagement with the other stationarycontact, the supply of current to the winding 243 of relay OR isinterrupted, while one of the zero-speed relays becomes deenergized.Thereafter, after a period of time the duration of which is determinedby thetime required for one Zero-speed relay to release and for theother to pick up, the other zero-speed relay becomes energized andeffects the supply of current to the winding 243 of relay CR.

The winding 243 of relay CR, therefore, is periodically supplied withcurrent, there being intervals between each supply period in which nocurrent is supplied. The intervals in which no current is supplied aresubstantially constant irrespectiveof the speed at which the axle 223 isrotated, as it is determined by the release time of one of thezero-speed relays plus the pick-up time of the other of these relays. Asthe frequency of current interruption increases due to the increase inthe speed of rotation of the axle 223, the portion of the total elapsedtime in which current is supplied to the winding 243 progressivelydiminishes, and the various parts of the apparatus are arranged andproportioned so that when the axle 223 is rotated at a speedcorresponding to a relatively low vehicle speed, such as 5 miles perhour, insufficient current is supplied to the winding 243 to energizethis winding to cause the contacts of the relay CR to be held in theirpicked up positions. At this point, therefore, and at higher vehiclespeeds, the re lay CR is no longer controlled by the zero-speed relaysA4 and A5. However, at extremely low vehicle speeds, due to operation ofthe zero-speed relays A4 and A5, the contact 263 of control relay CRwill be picked up and will establish a circuit to energize the brakecontrol magnet valve device Q and prevent this device from effecting anapplication of the brakes.

Similarly, when the vehicle is standing still, the contact 220 will bein engagement with one or the other of the stationary contacts 225 and226 with the result that the contacts of one or the other of thezero-speed relays will be picked up and will establish a circuit tosupply current to the winding 243 of relay CR to cause the contacts ofthis relay to be picked up and thus effect energization of the brakecontrol magnet valve device Q.

Under most operating conditions, before the vehicle speed has increasedto a value high enough to cause the zero-speed relays A4 and A5 toreduce the supply of current to the winding 243 of relay CR to a valueinsufficient to maintain the relay contacts picked up, the master relayMR will be caused to effect a sufficient supply of rectified current tothe Winding 264 of relay CR to maintain the relay contacts picked up.However, when the train control relay TCR is conditioned to permit highspeed operation, the master relay MR, as will be explained in detailhereinafter, is operated at a relatively slow speed with the result thatat comparatively low train speeds, the master relay MR will not supplysufficient current to the winding 264 of relay CRto maintain the relaycontacts picked up, and the energization of winding 243 being diminishedby operation of the relays A4 and A5, the relay contacts might becomereleased unless some supplementary means is provided to maintain thempicked up.

The transformer 238 and the winding 252 of relay CR are provided tomaintain the contacts of the relay CR picked up under thesecircumstances.

It will be seen that when the contact 255 of train control relay TCR isin its high speed position, as shown in Fig. 3 of the drawings, acircuit is established between wire 251, leading from the center tap ofthe secondary winding 249 of the transformer 238, to the wire 253connected to one terminal of the winding 252 of relay CR, while theother terminal of winding 252 is connected by wire 250 to one or theother portions of the transformer secondary winding 248. When axleoperated contact 220 moves out of engagement with one of the stationarycontacts associated therewith, the supply of current to one portion ofthe transformer primary winding kill 226 is'interrupted and theresulting change in flux in the transformer core induces a current inthe transformer secondary winding 249 which current is supplied to thewinding 252 of relay CR as explained above.

Similarly, on each movement of the contact 220 into engagement with astationary contact associated therewith, and on subsequent energizationofthe winding and picking up of the contacts of the one of thezero-speed relays which is energized over that stationary contact,current is supplied to a portion of the transformer primary winding 236and the resulting flux change in the transformer core causes current tobe induced in the transformer secondary winding and this current issupplied to the winding 252 of relay CR.

It will be seen, therefore, that the transformer 238 and associatedapparatus operates to effect the supply of an impulse of current to thewinding 252 of relay CR on each movement of contact 225 into or out ofengagement with either of the associated stationary contacts, that is,at twice the frequency of the impulses supplied to the winding 243 ofrelay CR. The various parts of the system are arranged and proportionedso that the impulses of current supplied to the winding 252 of relay CRwill energize this winding. to a degree sufficient to maintain thecontacts of the relay picked up until the axle 223 is rotated at asubstantially higher speed than is necessary to cause the degree ofenergization' of the winding 243 of relay CRto be reduced to such adegree that the winding 243 is no longer able to hold therelay contactspicked up.

It will be seen that when the axle 2 23 ismtated and the contact 220 iscaused to move between its two positions, the primary winding 249 oftransformer 238 is alternately energized from opposite ends. With eachsuch change in the end at which current is supplied to the transformerprimary winding, there is a reversal in the direction of flow of currentin the transformer primary winding and consequently a reversal 'in the.flux in the transformer 4.

As the speed of the axle 223 is increased, there is an increase in thefrequency of the reversals of current flow in the transformer primarywinding and a corresponding increase-in the impedance of the transformerprimary winding portions, and a corresponding decrease in the flow ofcurrent in the transformer primary windings, and also in the windings ofthe zero-speed relays A4 and A5 which are connected in series with thetransformer primary winding portions.

When the current flow in the circuits of the transformer primary windingportions is reduced to a predetermined value, the current flow in thewinding of one or the other of the zero-speed relays is insufficient tomaintain the contacts of the relay picked up or to cause them to bepicked up, and thereafter the contacts of this relay remain in theirreleased 'positions with theresult that one end portion of thetransformer secondary winding is thereafter constantly connected to thewire 250 leading to the winding 252 of relay CR.

On the subsequent supply of current in alternate directionsto theprimary winding 236 of transformer 238. alternating current is suppliedby the portion of'the transformer secondary winding controlled by thereleased one of the zero-speed relays to the wire 259 and thereby to thewinding252 of relay CR. This alternating current flowing in the winding252 of relay GR is not effective to create force to. assist inmaintaining the relay contacts picked up. The contacts of relay CR,therefore, will become released at this time unless sufiicient currentis supplied to the winding 264, as will hereinafter be explained indetail, to maintain the relay contacts picked up.

From the foregoing it will be, seen that when the vehicle is standingstill or is traveling at a very slow speed, the zero-speed relays A4 andtion of the winding 243 is reduced. At the same time, assuming thatcontact 255 of relay TCR is in the high speed position as shown in Fig.3 of the drawings, the degree of energization of the winding 252 ofrelay CR is increased as a result of operation of the transformer 238and associated apparatus. This increase in ener gization of the winding252 is suflicient to offset the reduction in energization of winding 243and causes the contacts of the relay CR to be main tained picked up. 1

Similarly, on a further increase in the vehicle speed so that the degreeof energization of winding 252is diminished, there is an increase in thedegree of energization of winding 264 for reasons to be hereinafterexplained in detail. This increase in the degree of energization ofwinding 264 is rapid enough to offset the decrease in the degree ofenergization of winding 252 with the result that the contacts of relayCR are main-- tained picked up until the speed of the vehicle isincreased to a degree such that winding 254 is no longer energizedsufficiently to maintain the contacts of relay CR picked up. 7

When the contact 255 of relay TCR is in its low speed position, .inwhich it engages stationary contact 266, or is in the medium speedposition, in which it engages contact 261, a circuit is establishedwhich short circuits one-half of the secondary winding 249 oftransformer 238. This circuit is traced from the center tap of thetransformer secondary winding 249 through wire 251, contact 255, contact266 or 261', and Wire 239 to the terminal at the left-hand end of thetransformer secondary winding 249.

. When the end portion of the transformer secondary winding is shortcircuited, no current is supplied from the transformer secondary windingtothe winding 252 of relay CR, and hence thiswinding is ineffective toassist in maintaining the contacts of the relay picked up.

However, at a time when the contact 255 of the train control relay TCRis in the low speed or medium speed position, the master relay MR isconditioned to operate at a substantially more rapid rate at the sametrain speed than the speed at whichvit operates when the contact 255 ofrelay TCR is in the'high speed position. Accordingly, the master relayMR will operate to supply current in sufficient degree to winding 264 ofreimpedance of the transformer primary winding,

there will be a greater flow of current in the circuits of thetransformer primary winding portions and a consequentmore rapid increasein the current in the windings of the zero-speed relays A4 and A5 withthe result that these relays will pick up more promptly. This results ina reduction in the duration of the periods in which no energy issupplied to the winding 243 of relay CR, and thereby slightly increasesthe degree of effective energization of this winding for a given trainspeed over that which is present when theportion of the transformersecondary winding is not short circuited.

The values of the various portions of the equipment are selected withthis characteristic of the system in view, and these values are suchthat with the contacts of relay TCR in their low or medium speedpositions, the supply of current by the zero-speed relays A4 and A5 tothe winding 243 of relay CR will be reduced to a low in efiective valuebefore the vehicle speed has been increased to a rate such that therelay MR becomes ineiiective to supply rectified current to the winding264 of relay CR.

The counting relays E5, E6, E1 and E8 employed in the system shown inFig. 3 of the drawings operate in a manner similar to the countingrelays employed in the system shown in Fig. 2 of the drawings. 'When themovable contacts of the train control relay TCR are in their hi speedpositions as shown in Fig. 3 of the drawings, the counting relays areoperated to go through a complete cycle of operation every fourrevolutions of the vehicle axle 223, while they effect operation of therelay MR once for every cycle of operation, that is, once for each fourrevolutions of the vehicle axle.

Similarly, when the contacts of relay TCR are in their medium speed orright-hand positions, the counting relays effect operation of the relayMR once every two revolutions'of the axle 223, while when the contactsof the relay TCR are in their center or low speed positions, thecounting relays also effect operation of the relay MR once every tworevolutions of the axle 223, but efiect energization of differentportions of the primary windings of transformer 219 than are energizedwhen the relay TCR is conditioned to permit medium speed movement of thetrain.

When the contacts of relay TCR are in their high speed positions asshown, the contact 215 of relay TCR'establishes connection from the wire216, leading from one terminal of the upper winding 218 of relay E6, towire 280 leading to a stationary contact which is engaged by a movablecontact 281 of the relay E5 when the contacts of relay E5 are picked up.

In addition, in this condition of the relay TCR, the movable contact 282thereof, which is constantly connected to the terminal B of the sourceof energy, engages a stationary Contact which. is connected by a wire283 to a movable contact 284 of the relay E1. The front point of contactof contact 284 is connected by a wire 285 to an intermediate tap on theprimary winding 286 of transformer 219, while the back point of contactof contact 284 is connected by a wire 288 to an intermediate tap on theprimary winding 290 of transformer 219.

One end terminal of primary winding 286 of transformer 219 is connectedby a wire 292 to one terminal of the armature winding 293 of thepolarized relay MR, while an end terminal of primary winding 290 oftransformer 219 is connected by a wire 295 to the armature winding 296of the relay MR. The other terminal of each of the windings 293 and 296of relay MB is connected to a branch of the wire 244, and thereby inseries with the ballast lamp 245 to the terminal C of the same source ofcurrent as that to which contact 282 of the train control relay TCR isconnected.

The relay MR employed in this figure of the drawings has a field winding349 and the armature windings 293 and 296. The armature windings 293 and296 of relay MR are mounted on a movable armature for operating therelay contact 298.

The armature windings 293 and 296 of relay MR are arranged so that whenone of these windings is energized, the movable contact 298 of the relayMB is caused to move to its left-hand position as shown in Fig. 3 of thedrawings, while when the other of these windings is energized, I

in one position engages a stationary contact which is connected by awire 302 to one terminal of the secondary winding 30l, while in theother position of the contact 298 it engages another stationary contactwhich is connected by way of a wire 303 to the other end terminal of thesecondary winding 30l of the transformer 219. The v contact 298 servesto rectify the current supplied from the secondary winding 303 oftransformer 219 with the result that current of one relative polarity ispredominant in the current which is supplied to the winding 264 of relayCR.

Operation of counting relays employed in the system shown in Fig. 3 ofthe drawings when train control relay is in its high speed position Inthe operation of the counting relays with the train control relay TCRconditioned, as shown, to permit high speed running, assuming that allof the counting relays are deenergized, then on the first operation ofthe contact 22l, which is assumed to be movement of the contact 22! intoengagement with contact 210, a circuit is established to energize theupper winding 305 of relay E5. This circuit is traced from terminal B,contact 22!, contact 210-, wire 304, winding 305 of relay E5, wire 306,back point of contact 308 of relay E8, and wire M0 to terminal C of thesource of current. The winding 305 of relay E5, therefore, is energizedand the contacts 3 and 28! of relay E5 are picked up and engage theirfront points of contact.

On the'second operation of contact 22l, which is movement of contact 22|out of engagement with contact 210 and into engagement with contact 212,the circuit to wire 304 is interrupted, while a circuit is establishedto wire 3l2. On the completion of the circuit to wire 3l2, a circuit iscompleted by a branch of this wire to the lower winding 3|4 of relay E5,and then by a wire 3l5 to front point of contact of contact 3 and abranch of wire 3|0 to terminal C.

In addition, on this establishment of a circuit to the wire 312, acircuit is completed through the upper winding 218 of relay E6, andthence by wire 216, contact 215 of relay TCR, wire 280, front point ofcontact of contact 281 of relay E5 and a branch of the wire 310 toterminal C. The

winding 218 of relay E0, therefore, will be energized and the movablecontacts 301 and 303 of this relay are picked up and engage their frontpoints of contact. I

On the third operation of contact 22!, that is, movement ofthe contactout of engagement with the stationarycontact 212 and into engagementwith the stationary contact 210, the upper winding 335 of relay E5 isagain energized to maintain the contacts of this relay picked up, whilea circuit is completed which includes the wire- 304, the lower winding 316 of relay Efi, wire 3H, and front point of contact 309 of relay E6, abranch of the'wire 3I0, and the terminal C of the source of current.

As the winding 310 of relay E6 is energized, the movable contacts 301and 309 of this relay are maintained picked up.

In addition, on this third operation of the contact 32!, with theresultant-completion of a circuit to the wire 304, a circuit iscompleted through the upper winding 318' of relay E1 and thence by awire M9 and front point of contact 301 of relay E5 to a branch of thewire 310 and to terminal C of thesourceof current. As the winding 318 ofrelay El isenergized, the contacts 322 and 323 of relay El will bepicked up and will engage their from points of contact.

On the fourth operation of contact 22!, that is, movement out ofengagement with contact and intoengagement withcontact 212, the windingtilt of relay Eliand the winding 218 of are energized over thepreviously traced circuits withthe result that the movable contacts ofthese relays are maintained picked up. In addition, on thisfourth'operation of contact ii i, a circuit is'cein-pleted whichincludes the wire -ower winding 324 of winding E'i, wire 325, frontpoint of contact of contact 322 of relay El and a branch ofthe wire3liland to the terminal C of the source of current. As the winding 324is energized, themovable contacts 322 and i523 of'relay E'laremaintainedpicked up.

In addition, on this fourth operation of con--' tact Edi, that is,movement of contact 221 into engagement with contact 212 to which isconnected the wire 312, a circuit is completed through the upper winding32"! of relay E8, wire 328, front point-of contact 323 of relay El,which at this 1 time is picked up, and a branch of the wire Bill to theterminal C of the source of current. As the winding 321- of the relay E3is energized, the movable contact 358- thereof is moved out ofengagement with its back point of contact and into engagement with itsfront point of contact.

On'the fifth operation of contact 22L that is, movement of contact 22!out of engagement with contact 212 and into engagement with contactElli], a circuit is again completed from the terminal B to the wire 304with the result that the winding 3l5 of relay E5 and the winding N8 ofrelay El are again energized through the previously traced circuits forthese windings.

At this time, however, the winding 3-05 of re- "lay Ell is notenergized'since the circuit of this 2iii,' a circuit is completedthrough the wire 304- and the winding 330 of relay E8, and thence by awire 335 and the front point of contact of i. no

contact W3 of relay E8 to a branch of the wire Sit: and to the terminalC of the source of ourrent. As the winding 330 of relay E8 is energized,the contact 308 of relay E8 is maintained picked On the sixth operationof contact 22!, that is, movement of the contact out of engagement withcontact 210 and into engagement with contact 212, a circuit is completedfrom the terminal B to wire M2 and the winding 324 of relay El, andwinding 32'! of relay E8 are energized over the previously tracedcircuits for these windings. At thistime, as the movable contact 3 ofrelay E5 is in. its released position, the circuit through the winding3M of the relay E5 is interrupted and this winding remains deenergized.

Similarly, as the contact 28! of relay E5 is in its released position,the circuit through the winding 218 of relay E is interrupted and thiswinding does not become energized. Accordingly, the contacts 301' and309 of relay E6 will become released upon this the sixth operation ofcontact 22!.

On the seventh operation of contact 22l, that is, movement of thecontact out of engagement with contact 21 2 and into engagement with contact 210, current is supplied to the winding 330 offrelay E8 over thepreviously traced circuit. At this time, as the contact 303 of the relayE3 is in its engagement with its front point of contact, the circuit ofthe winding 305 of relay E5 is interrupted and this winding remainsdeenergized.

Similarly, as the contact 309 of relay E5 is in its" released position,the circuit through the lower winding 3|6 of relay E6 is interrupted andthe winding 3T6 remains deenergized and the contacts of relay E6 remainin their released positions.

Likewise, as the contact 30*? of relay E8 is in its released position,the circuit through the winding 3! of relay El is interrupted and thiswinding does not become energized on the coinpletion of the circuit tothe wire 3%. As the winding 324 of relay ET is deenergized on interruption of the circuit to the wire M2, the movable contacts 322 and 323of relay El become released.

On the eighth operation of contact 2.21, that is, movement out ofengagement with. contact 370: andinto engagement with contact 212, thesupply of current to winding 333; of relay E3 is interrupted, while atthis time. as the circuit through the winding 32'! of relay E3v isinterrupted since contact 3230f relay E1 is in its released 30- sition,the movable contact 308 of relay E8 becomes released and engages itsback point of contact. I 7

Likewise at this time the circuit through the winding 324 of relay El isinterrupted because contact 322 of relay ET is released, while thecircuit through the winding of relay E3 is interrupted because contact32! of relay is released. In' addition, the circuit through the winding314- of relay E5 is interrupted as contact 3! I ofrelay E5 is released.

' It will be seen, therefore, that on the eighth operation of contact221,- allof the relays E5, E1 and E8 are released.

On the ninth operation of contact ZZI, which isthe first operation in anew cycle of operation, the contact 221 is moved into engagementwith thecontact 270 thereby establishing a circuit from terminal'B' to the wire304, through the upper winding 305 of" relay E5, thence by the wire 306to back point of contact of contact 338, which. at; this: time is: in.its. released position,

